Self-consistent simulations of a four-gated vertical quantum dot

We present three-dimensional (3D) finite-element simulations of symmetric and asymmetric chargings of a four-gated vertical quantum dot (4GVQD) structure. Emphasis is placed on 3D device effects with no a priori assumption about, the shape of the electron confining potential (CP). We show that, by acting asymmetrically on the electric gates, small elliptic deformations in the electron CP are induced with little changes in the addition energy spectrum of the 4GVQD. Charging spin sequences are, however, strongly modified by small deformations, and can therefore be controlled electrostatically by tuning the gates accordingly.